# What type of intermolecular forces will dominate Diethyl ether?

Is Diethyl ether (also known as ethyl ether) a polar molecule? What type of intermolecular forces dominate it? Dipole-Dipole Interactions, London Dispersion Forces or Hydrogen Bonding? Please Explain.

• Take a look at these pictures. en.wikipedia.org/wiki/Diethyl_ether Based on only the figures, can you make some deductions as to what it might be? Please offer some reasoning and we'll be more inclined to help you. – LordStryker Apr 8 '14 at 15:59
• Most organic molecules are polar by definition - they have a dipole moment (ethers included). In the context of solvents, polar refers to solvents with higher polarity, and non-polar to solvents with lower polarity. It's relative. Diethyl ether is at the lower end of the polarity scale and so is generally considered a 'non-polar' solvent . This is what I read recently about Diethyl ether's polarity. Is it correct? – azaidi Apr 8 '14 at 16:26
• Okay, so diethyl ether has a small dipole. So, now what about LDF and H-bonding? You're getting closer. – LordStryker Apr 8 '14 at 16:32
• As Diethyl ether has a very low polarity, if any, so, H-bonding is not possible, I suppose. LDF are present in all either polar or non polar molecules, so they are present here too. As it is slightly polar so it may also exhibit weak dipole-dipole interactions. – azaidi Apr 8 '14 at 16:41
• Carbon-donated hydrogen bonding is a very real thing but these are very, very weak non-covalent interactions. So yes, I think your reasoning that H-bonding isn't possible is fine. LDF is present in every chemical system but these are weak as well (there are exceptions where LDF may be significant in the binding energies of certain dispersion-dominated molecules). Quick question: Is diethyl ether soluble in water? If so, what force that you listed would most likely contribute to this? – LordStryker Apr 8 '14 at 18:48

London dispersion forces, which result from short-lived dipoles induced by fluctuations in the electron shell of molecules, are also present. They are responsible for the weak interactions between the alkyl chains, like in other alkanes and non-polar molecules. The permanent dipoles can also interact with each other, in the form of intermolecular attractive interactions between centers with $\delta+$ and $\delta-$ partial charge (and likewise repulsion between centers of equal partial charge).